elang/compiler/analysis: Make |NameTreeBuilder| not to use |ast::ClassBody::owner()| for a preparation of deprecating |ast::Class|.
elang/compiler/analysis: Make |NameTreeBuilder| not to use |ast::ClassBody::owner()| for a preparation of deprecating |ast::Class|.

eval1749/elang,eval1749/elang,eval1749/elang,eval1749/elang,eval1749/elang